[PATCH] D114784: [SCEV] Track backedge taken count users (NFCI)

[Nikita Popov via Phabricator via llvm-commits]

nikic created this revision.
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Track which SCEVs are used as ExactNotTaken counts in BackedgeTakenInfo structures, so we can directly determine which loops need to be invalidated, rather than iterating over all BECounts.

This gives a small compile-time improvement on average (https://llvm-compile-time-tracker.com/compare.php?from=77dd579827f2e7574be4bbf3f94a48930e7b094f&to=72d45d2131f55751be7654e5d13115fe5b150dbb&stat=instructions), but the motivation here is more to ensure there are no degenerate cases, if the number of backedge taken counts is large.


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D114784

Files:
  llvm/include/llvm/Analysis/ScalarEvolution.h
  llvm/lib/Analysis/ScalarEvolution.cpp

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